Fish Deeper app features three different color modes: Classic, Day and Night. So you’ll always be able to easily see the sonar readings on your phone screen in any lightning conditions.
When using PRO / PRO+ / CHIRP sonars, the brightest color on the screen will always represent a strong ultrasound reflection from an object, meaning that the brighter the color is - the harder the object was. The bottom will always have the brightest color, since it reflects ultrasound in the strongest manner. It doesn't matter which screen color mode you use - brightest colors on all of them will represent the strongest ultrasound return.
See below example: bottom has the most noticeable color in all 3 color modes. Bigger fishes are also seen as thick lines of bright color.
Identifying bottom hardness based on the colors
Brightness of colors on the screen play an important role when identifying underwater objects, bottom features and fishes.
Color is closely related to how strong the echoes return to the sonar. Density and how hard an object is are both very important factors in echo return strength. The stronger the echo is when it returns, the brighter the color used on the fish finder display.
The lakebed, or the bottom of whatever body of water you may be in, is often the brightest of all discovered objects. The bottom of the lake, river, pond, or wherever you are may be either be a thick, bold line, or a thin, light line. If it is a light line, then it is a softer ground material like clay. A thicker, bold line means that the material on the bottom of whatever body of water you are in is a lot harder and usually less porous.
For best results in identifying the strengths of echos, you should use a high-frequency beam: Deeper PRO/PRO+: Narrow 290 kHz beam; Deeper CHIRP+: Narrow 675 kHz or Mid 590 kHz beam.
Examples of soft vs hard bottoms (using Deeper CHIRP+)
In the above example, we can see a soft bottom (clay) near the shore, with thick vegetation sticking out of it. Note that the bottom line is thin, and of red color.
In this example, the bottom is much harder. Note that the bottom line is much thicker, and is yellow (which means a strong echo return).